Refrigerating apparatus



J. KIRGAN Filed sept.. 1o, 1957 HIS ATTORNEY.

REFRIGERATING APPARATUS J9 ya?,

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Patented Dec. 19, 1939 UNITED STATES PATENT OFFICE REFRIGERATING APPARATUS tion of New Jersey Application September 10, 1937, Serial No. 163,187

4 Claims.

rIhis invention relates to rerigerating apparatus, but more particularly to water-vapor rerigeratng apparatus and the parts thereof through which the cold water ows from the evaporator to the circulating pump to be impelled to a place of use.

An object of the invention is to assure an adequate supply of liquid for the pump.

Another object is to reduce the frictonal resistance of the passages leading to the pump.

A further object is to obviate erratic iluctuations in the iiow of water through the evaporator to the pump.

Other objects will be in part obvious and in part pointed out hereinafter.

In the accompanying drawing in which like numerals denote the same parts,

Figure 1 is an elevation, partly in section, of reirigerating apparatus constructed in accordance with the practice of the invention,

Figure 2 is a sectional view or the apparatus taken through Figure 1 on the line 2--2,

Figure 3 is a sectional view of the evaporator vessel taken through Figure 1 on the line 3 3, and

Figure Li is a sectional view of the evaporator vessel taken at right angles to Figure 3 and through Figure 2 on the line 4-4.

Referring more particularly to Figures l and 2 oi the drawing, 2G designates the evaporator vessel of a water-vapor refrigerating apparatus, and 2l and 22 its inlet and discharge conduits, respectively. At 23 is a motor-driven pump interposed in the discharge conduit 22,

Only fragmentary portions of the inlet and discharge conduits are shown, for convenience of illustration, and it is to be understood that the discharge conduit 22 forms part of a refrigerant circuit including one or more units, such as air conditioners or the like, through which the passage or" liquid may be controlled by suitable valves. The inlet conduit 2i may lead from any suitable source of liquid or may serve to return the warmed liquid from the air conditioners to the evaporator vessel 2G. It is also to be understood that the conduit system is of the open type; that is, at a point in its circuit from the pump 23 through the air conditioners and back to the vessel 2Q, but preferably in the air conditioners or on the down stream side thereof, the liquid flowing in the conduits is exposed to atmospheric pressure.

1n apparatus of this character the refrigerant liquid, which may be water, is discharged into the evaporator vessel and exposed to reduced pressure to be partially vaporized and cooled. The vapor is removed from the vessel 2U and the reduced pressure is maintained therein by suitable evacuators, shown as steam ejectors 39, which discharge the vapor at somewhat increased pressure into a condenser d0. The cold water is drawn off through the conduit 22. Over a period of time, however, the requirements for the cold water may vary widely and some or the air conditioners may operate but intermittently. Obviously, when operating under these conditions, the output and capacity of the pump 23 vary over a considerable range and more or less in proportion to the number of units in operation. If, then one or more of the units is suddenly started or stopped, a severe change in the capacity of the purnp occurs which, if not promptly compensated by a corresponding change in the flow or liquid to the evaporator vessel 20, results in ooding or draining of the vessel, variations in the static head on the pump 23 and a general loss of pressure balance throughout the apparatus.

In order to overcome these undesirable eects, the present invention provides for an adequate supply of liquid for the pump, for an adequate control of the liquid flowing through the evaporator, and for a material reduction in the frictional resistance or" the passages through the evaporator and leading to the pump.

In accordance with the practice of the invention, there is interposed in the discharge conduit 22 between the vaporization region of the evaporator vessel 2S and the pump 23. a storage chamber or reservoir 24 through which all the cold water passes from the evaporator to the pump. This reservoir serves to store water in adequate amounts for temporarily supplying the needs of the pump 23 should its capacity increase and for temporarily absorbing excess Water from the evaporator should the capacity of the pump decrease. The ilow of liquid through the vessel 2S is preferably controlled by suitable means, more fully described hereinafter, in accordance with fluctuations in the level of the liquid in the reservoir 24.

In the preferred construction, the evaporator vessel 2i! houses one or more vaporization chamhers 25 and the reservoir chamber 24, and the chambers are so spaced and arranged that the passages to and from the chambers are large and the frictional resistance thereof is very low.

Referring more particularly to Figures 3 and 4 of the drawing, 2.6 and 2l designate opposite side walls of the vessel 20, 28 and 29 designate opposite end walls thereof, and 3E and 3| designate its top and bottom walls, respectively.

A vertical partition 32 positioned between and parallel to the side walls 26 and 2, but nearest wall 2l, extends upwardly from the bottom wall 3i to a point just below the top wall 3. This partition 32 cooperates with the end walls 28 and 29 and with the side wall 2l to denne a compartment 33 into the bottom of which the inlet conduit 2l opens through a port 3G in the wall 2l'. The top of the partition 32 forms a Weir 35 in each vaporization chamber 25 and may, if desired, have a series of openings 36 therein to deliver water in a more or less divided state from the compartment 33 into the chambers 25.

A horizontal partition 3i positioned between the top and bottom walls 3i! and 3l is aflixed to 1rie partition 32 and the end walls 28 and 23 and extends from partition 32 toward but not quite to the side wall 2li. The vaporization chambers are in the region above this horizontal partition 3l, and the partition serves as a shelf along which the water flows to be delivered to the reservoir chamber 2li which is beneath the partition. Ports 38 in the top wall 3i) open from these chambers 25 into the vapor evacuators 39.

A vertical partition lil depending from the end of partition 3l' adjacent the side wall 26 is parallel to and spaced from wall 2&5, extends between end walls 23 and 29 .and terminates short of the bottom wail 3i to define a space 133 and a passage 0,2 from the chambers 25 into the reservoir 24. The partitions 32, 3l and di and bottom wall 3l serve to denne the reservoir chamber 2d. The bottom of partition 4I is below the normal level of liquid in the reservoir 24.

Two vaporization chambers 25 .are shown and these are separated by a vertical partition lli positioned vbetween and parallel to the end walls 28 and 29. The partition it extends between the side walls 26 and 2l from the top wall 3l! to the partition 3l and adjacent walls 23 and 2l has two depending portions lib and l5 of the same width as and projecting downward into the space i3 and compartment 33, respectively. These depending portions each terminate short of the bottom wall 3l and divide the space 43 into separate passages leading from each chamber 25 into the reservoir 2d and divide the upper part of compartment 33 into separate passages or inlet wells lil, one for each chamber 2o. The liquid in these passages serves to seal one chamber from another and each of the passages is sufficiently deep that, when an ejector 39 is shut ofi to render a chamber 25 inactive, the pressure in the chamoer may be increased at least to the discharge pressure of the vapor evacuators 39 without breaking these liquid seals.

An outlet lll in the bottom wall 3l opens from the reservoir 23 into the conduit 22. The capacities of the passages 43 and reservoir 2d are large and the frictional resistance thereof is low. Furthermore the pump 23 may be placed directly adjacent the outlet i8 which materially reduces the friction of the pipe 22. The static'head on the pump will, therefore, closely approach the actual submergence head thereon.

Referring again to Figures l and 2, the ilow f liquid through the vessel 2G is arranged to be controlled in accordance with fluctuations in the level of the water in the reservoir 24. To this end, a pressure-responsive valve is interposed in the inlet conduit 2| and comprises a valve member 49 in a suitable casing, a spring 5l! to urge the valve member i8 toward closed position, and

a diaphragm l against which pressure is ex-r erted to open the valve in opposition to the force of the spring 5t. The source of pressure fluid for actuating the valve ispreferably water discharged by the pump 23 and a pipe 52 leads from the conduit 22 at the discharge side of the pump to the valve for this purpose.

The pipe 52 has a branch 53 extending and opening into the reservoir chamber 2d preferably above the normal level of liquid therein, and within the chamber 24 is a valve 5d interposed in the branch pipe 53 for controlling the pressure of the liquid acting on the diaphragm 5l. Connected to this valve 5d is a iioat 55 which rides on the surface of the liquid in the reservoir and actuates the valve 513.

Since all the chambers in the vessel 2t are in communication through the permanently open passages d3 and the chambers 25 are subjected to a Very high vacuum, a means is provided for subjecting the reservoir chamber 24 to a somewhat higher pressure than the pressure in .any vaporization chamber to enable liquid to lill the chamber 2li to the desired degree and to prevent further vaporization of the liquid in the reservoir 2li. To this end the chamber 24 is vented by a pipe 5S to the condenser lib. The difference in pressure between a chamber 25 and the reservoir chamber 2d is manifested by the difference in liquid levei therein and these levels are maintained more or less constant by the action of the float 55.

The operation of the apparatus is as follows: If it is rst assumed that all the units supplied by the conduit 22 are in operation, liquid will course through the conduits 22 and 2l and chambers 25 and in the normal manner, chambers 2li and 24 will be filled to normal operating levels, the liquid will be maintained at these levels by the action of the oat 55 and valve 6:9, and the pump will operate at full capacity.

If then one or more of the units is stopped and liquid ceases to flow therethrough the output and capacity of the pump 23 will be reduced proportionately. This reduction occurs almost instantaneously and causes a reduction in the velocity of flow through the conduit 22 from the reservoir 2li. The liquid in the conduit 2l being, however, under its own head, continues to flow momentarily at its original velocity and consequently attempts to ll the chambers in the Vessel 2El, raising the liquid levels therein. The float 55 rises, opens the valve somewhat and relieves the pressure in the pipe 53 to cause the valve 29 to move toward closed position, thereby decelerating Vthe liow of liquid to the vessel 2G to compensate for the change in the capacity of the pump 23.

The excess liquid which entered the vessel 26 during the brief interval required by the float 55 and valve i3 to decelerate the velocity of flow in the inlet conduit 2i is stored in the reservoir 2d, but the large capacity thereof prevents any excessive change in liquid level or in the static head on the pump 23.

If the pump capacity increases, as when some of the units fed by the conduit 22 are started, the increased demand of the pump will be supplied momentarily from the reservoir 24, causing a lower liquid level therein and consequently an increased opening of the valve Q9. The reservoir will continue to supply the needs of the pump during the brief interval required for the velocity of ow in the conduit 2| to accelerate to a value compensating for the change in pump capacity, but again the large capacity of the reservoir prevents any excessive change in liquid levels or in the static head on the pump.

Inasmuch as the reservoir 24 is interposed directly in the path of flow of the liquid from the chambers 25 to the pump 23, all of the cold or treated water must pass through the reservoir and directly act on the iioat 55 and be directly influenced by any change in the operating characteristic of the pump 23. Thus when any change in the capacity or" the pump occurs, its entire ei"- ect is manifested by changes in the liquid level in the reservoir 251i, but the large capacity of the reservoir obi/lates excessive fluctuations oi the level therein, prevents sudden draining or flooding of the vessel 29 and enables the oat 55 and the action of valve 5S to closely follow the variations in pump capacity.

I claim:

l. In refrigerating apparatus, an evaporator wherein liquid is treated, inlet means to admit liquid to the evaporator, a pump, conduit means for the treated liquid leading from the evaporator to the pump, means interposed in the conduit means and defining a reservoir in the path of liquid flow and through which all the treated liquid flows, pressure-responsive means actuated by liquid discharged by the pump to control the -lcw o liquid through the inlet means, and means acting responsively to variations in the level of the liquid in the reservoir to control the pressure of the liquid actuating said pressure-responsive means.

2. in refrigerating apparatus, a vessel having at least two evaporator chambers, inlet means to admit liquid to the evaporator chambers, means in said vessel defining a common reservoir to receive liquid ilowing from each evaporator chamber, means to selectively render any evaporator chamber active, means to subject the reservoir to a pressure equivalent to the pressure of an inactive evaporator chamber to prevent removal of all liquid from an inactive evaporator chamber, means to control the inlet means in accordance With variations in the level of liquid in the reservoir, and outlet means for removing liquid from the reservoir.

3. In refrigerating apparatus, a vessel having at least two liquid vaporization chambers therein, a reservoir chamber in the vessel beneath and common to all the vaporization chambers, inlet means to admit liquid to the vaporization chambers, a vapor evacuator for each vaporization chamber to reduce the pressure therein, means to separately control actuation of each evacuator, open conduits for unvaporized liquid leading from each vaporization chamber and opening into the reservoir chamber below the normal level of liquid in the reservoir chamber, an outlet conduit for the reservoir chamber, a condenser to which the evacuators discharge, means to subject the reser- Voir chamber to the condenser pressure and to thus prevent all the liquid in a chamber whose evacuator has een rendered inactive from flowing out of the open conduit into the reservoir, and float and valve means for controlling the inlet means in accordance with variations in the level of liquid in the reservoir chamber.

e. In refrigerating apparatus, a vessel having a plurality or vaporization chambers in the upper part thereof and a reservoir chamber beneath the vaporiaation chambers, inlet means to admit liquid to the vaporization chambers, vapor evacuators for the vaporizaticn chambers, a condenser to which the evacuators discharge, means extending into the reservoir chamber to convey all unvaporized liquid from the vaporization chambers into the reservoir chamber, an outlet conduit from the reservoir chamber, and a conduit connecting the condenser and common reservoir to subject the common reservoir to condenser pressure whereby a liquid seal may be maintained in said means extending into the reservoir chamber at all times.

JOHN KIRGAN. 

